Domestic boiler



Sept. 7, 1937. l F. W. RIEHL 2,092,334

DOMESTIC BOILER Filed March 15, 1954 3 Sheets-Sheet 1 A TTORNEY STACK WMM/M Sem. 7, 1937. F. W. RIEHL DOMESTIC BOILER Filed March 15, 1934 3 Sheets-Sheet 2 INVENTOR www LKN R W w Sept. 7, 1937. F. w. RIEHL DOMESTIC BOILER 3 Sheets-Sheet 3 Filedl March l5, 1934 NAN.

L; RM /MY WW, o NK w A R M MB Patented Sept. 7, 1937 UNITED STATES PATENT DFFICE 2,092,334 DOMESTIC BolLEa Frederick W. Riehl, Lynbrook, N. Y.

Application March 15, 1934, Serial l\lo. '715,647 10 Claims.V (Cl. 122-142) This invention relates to improvements in domestic furnaces, particularly to furnaces involving the use of fluid fuel burners.

Considerable advancement has been made in the adaptation of oil burners to existing house heating furnaces. Very `little has been accomplished however in the adaptation of a furnace or boiler to the oil burner and its particular functions Likewise, while an oil burner may be installed in an'existing house boiler, the solution of the domestic hot water problem for summer time has not been solved in a satisfactory Way.

The primary object of the present invention `is 'thereforel to provide an improved domestic heating plant particularly adapted to burn oil or gas as fuel. `A further object ofthe invention is the provi- `sion Tof a boiler or water heater particularly adapted to effectively utilize the full effectl of a fluid-fuel burner.

Afurther object of the invention is to provide a steam or hot water Vheater which may be readily converted into a heater for domestic hot'Water.

With these and other objects and advantages in view the invention will be best understood by referring toy the following detailed description taken in conjunction with the accompanying drawings in which:

Fig. `1 is a front elevational view of a boiler constructed in accordance with the features of the present invention.

, Fig. 2 is a broken side elevational view of the `upper `half of the boiler shown in Fig. 1, looking from the right.

Fig. 3 'is a vertical cross sectional view of the boiler `shown in Fig. 1, showing details of construction.

Fig. 4 is a broken vertical sectional view of the boiler taken on the line 4-4 of Fig. 3. n Fig. 5 is a horizontal sectional view i the line 5-5 of Fig. 3. i

Fig. 6 is a view similar to that of Fig. 4 taken "on the line 6-6 of Fig. 3. Fig. 7 is a view similar to that of Fig. 6 taken on the line 'l--l of Fig'. 3, looking toward the left, Fig. 8 is a view similar to that-of Fig. 'l taken on the line 8--8 of Fig. 3.

Fig. 9 shows a modied form of the boiler shown in Fig. 1.

Fig. 10 is a broken sectional view taken on the line lll-I0 of Fig. 9. Fig. 11 is a sectional view taken on the. line II-H of. Fig. 9.

Referring to the drawings in which like ref- ,erence characters designate-like or correspond- `inglparts o-f the apparatus, the boiler plant as g shown inpFigures lzand 2..'comprises in general a taken on combustion chamber section 2 and a main boiler shell 4. The boiler shell is provided with a pressure gage 6, a liquid level gage 8, a Water level cock IU and an oil skimmer I2. The shell 4 also contains a domestic hot water heating coil com-1,.-

prising one or more interconnected tubes I4 provided with inlet and outlet as shown in Figure 1. Water is supplied to the boiler through a line I8 and condensate returned through` a line 20, while steam is discharged through a line 22.A The combustion section is provided with a port hole 24 and the boiler shell with a safety valve 26. Y

The boiler shell itself as described hereinafter, contains a relatively small amount of water to be heated and therefore chamber 28 containing a' floating water supply is provided to maintain the necessary water level in the boiler, regardless of the fact that a substantial proportion is removed in the form of steam. The floating water supply in chamber 28 is not actually heated`VV in the system, but serves as a reserve supply to prevent undue fluctuations in the water level in the boiler. The chamber 28 is connected into the line I8 by a pipe 30 and to the steam. space of the boiler by a pressure equalizing line 32.

In Fig. 3 the boiler is shown in vertical section revealing a conventional rotary type oil burner 34 mounted at the base of the combustion space 2, which is lined with fire brick 36 (see also Fig.

5), packed in with asbestos cement 38. The combustion gases from the space 2'pass into a heating compartment 4|] in the lower part of. the boiler shell 4, then through large horizontal flue tubes 42 in each of which is mounted an inclined water tube 44. a second heating compartment 46 in the shell 4. The water tubes 44 open into the shell 4 through the opposite outer walls of heating compartments and V46. From the compartment 46 the combustion gases pass through a plurality of in'- clined tubes 48 which discharge into a flue gas compartment 5U, and are nally passed to a stack by means` of a connecting pipe 52. Fire tubes 42 may be cleaned from capped clean-out tubes 54 which open into the compartment 40 opposite the ends of tubes 42. The steam outlet 22 is provided with a perforated shield 56 mounted inside the shell 4.

As shown by Figs. 3, 4 and 6 to 8, the boiler shell is so constructed that the heating compartments Ysection is provided with a drain plug and connection 60, while the central and right sections The tubes 42 connect into of the boiler may be drained through lines I8 and 20.

In the operation of the boiler the combustion gases enter heating compartment 40, pass around inclined water tubes 44, through ue tubes 42 into heating compartment 46 and finally through inclined ue tubes 48. The intense heating of the water in tubes 44 causes the formation of steam and the flow of water to the left in these tubes, that is, counter-current to the flow of combustion gases. The water and steam from tubes 44 are discharged into the left section or chamber of the boiler, from which the water flows to the right along ilue tubes 48, counter-current to the combustion gases flowing therethrough. Since tubes 44 draw water from the right section of the boiler, water from the central Zone or section of the boiler may return thereto over heating compartment 46 and through conduit 58. Condensate from the house radiators is also introduced into the right section through the line I 8, so that this section of the boiler may be considered the supply chamber or cold section of the boiler cycle.

The extensive heating surface provided by the walls of compartments 40 and 46 and tubes 42, 44 and 48, together with the counter-current flow of combustion gases and water provide a very efcient arrangement for utilizing fluid fuels in intermittent domestic house heating systems.

The boiler of the present invention is provided with a low water cut off comprising a fusible electrode which is connected into the fluid fuel burner circuit. This electrode 62 (Fig. 2) mounted in the lower part of compartment 36 may be placed in any suitable part of the boiler. The plug is connected into the burner circuit by leads 68 and l0. The electrode 62 is inserted into a socket so that the fusible element projects into compartment 46. If the water in the boiler falls too low the temperature of the combustion gases will rise and melt the fusible element, thereby breaking the electrical circuit to the fluid fuel burner motor or control, and stopping the burner.

As indicated by the drawings the boiler furnace is preferably made up of standard steel plate and pipe, cut and welded together in the manner shown. In a specic instance in providing a boiler for a small house the shell 4 may comprise a section of steel pipe 22 inches in diameter and 2 feet six inches long, while the casing for the combustion chamber is made from a similar length of 28 inches steel pipe. Tubes 44 are preferably 11/2 inch boiler tubes set at a pitch of about one and one eighth inch per foot. Tubes 42 are about 4 inches in diameter and set horizontal, while tubes 48 are 2 inches and set at an angle.

When the boiler furnace is :not in use for heating the house, as in the summer time, it may be quickly shifted to the heating of water for domestic use, which is accomplished by shifting valve settings in lines I8 and 22. A cold water supply line 'I4 connects into the line I8 through a valve '|6, and a hot water discharge line '|8 connects into steam line 22 through a valve 80. The valves "IS and 80 are interconnected with a bar or lever 82 which may be locked in the desired position by means of a locking device 84. The upper extending part of the lever 82 is preferably connected to certain electrical switches on a switch panel 86. The switches or electrical contacts on the panel 86 include the burner connections to the house thermostat and its connections to the aquastat. In one position the lever 82 fixes valves 'I6 and 80 to cut off lines I4 and 'I8 and open lines I8 and 22, breaks the electrical connection between the burner and aquastat and makes an electrical connection between the burner and house thermostat. With this setting the furnace will be operated to heat the house in accordance with the demand of the thermostat. When the lever 82 is set in the opposite position lines I8 and 22 are cut off and lines 'I4 and 'I8 are connected into the boiler, the electrical connection between the burner and aquastat is made and the electrical connection between the burner and thermostat is broken. With this setting of lever 82 the furnace will be operated to supply hot water in accordance with the demand of the aquastat. When the seasonal shift of lever 82 is made it is preferably locked in position, and in a shift to steam heating the water in the shell 4 will be adjusted to the proper level.

Figures 9, 10 and 11 show the boiler of the present invention with certain added features. While the flue gas temperature in chamber 50 (Fig. 3) may be comparatively low because of the long path of flow through the boiler, considerable heat may be recovered by the use of a heat exchanger I 00 shown in Figs. 9 and 11. This heat exchanger is preferably attached directly to the chamber 50 which receives the flue gas from the boiler. The unit |00 comprises a plurality of vertical finned tubes |02 through which air is passed in indirect heat exchange with flue gas. Air may be preheated for the burner by drawing it through an inlet |04, into a header chamber |06, downward through tubes |02 to the left in Fig. 11, into a header chamber |08, upwardly through other tubes |02 into a header chamber 1 IIO, downwardly through still other tubes |02 into a header chamber I |2 and then out to the burner through a conduit II4. The remainder of the tubes |02 are used to heat air for the house by drawing air from outside the house through an inlet conduit I I 6 into a header chamber |I8, upwardly through certain of the tubes |02 into a header chamber |20 and then out to the room through a hot air conduit |22.

The furnace construction of Figs. 9 and 10 is shown completely insulated. This furnace also includes a combination boiler support, combustion chamber and domestic water tank and heater. The base of the furnace therefore comprises inner and outer concentric cylinder sections |24 and |26 welded together with suitable end plates to form an annular chamber |28 for heating water. The sides of the double walled chamber |28 which extend up around the boiler shell 4 form a saddle which serves to retain the boiler shell in position. Cold water to be heated is admitted to chamber |28 through inlet |30, while hot water is withdrawn through a pipe |32 which connects with the side high points of chamber |28 through branch pipes |34. Pipe |32 may be connected to a hot water tank or directly to the house supply lines.

The combustion chamber within the hot water heating chamber I 28 comprises one or more cylindrical refractory tile |36 adapted to cover a very substantial portion of the inner wall of chamber |28. However suicient of the wall |24 is left exposed to the combustion gases from the burner to give hot water of the desired amount and temperature. The combustion gases rst heat the water in chamber |28 and then the boiler. A clean-out and observation door |38 is provided in the wall of the combustion chamber.

The heat exchanger or the hot water chamber |28 or both, may be used in the form of apparatus shown in Figs. 1 to 3.

The boiler shell 4 shown in Figs. 9 and 10 is of the same constructionas that shown in Figs. 1, 2 and 3. While different typ-es of burners are shown it is to be understood that the type of fluid fuel burner is immaterial. However, as indicated in the foregoing description the burner is to be operated automatically in response to a demand for heat in the house. No claim is here made to the automatic burner operation as such since such systems and operations are well known.

From the foregoing description it is apparent that various changes may be made in the ap' paratus without departing from the spirit and scope of the invention. Furthermore the invention is not to be limited to the specific examples described except as so limited by the claims.

Having thus described the invention in its preferred form what is claimed as new is:

l. A house heating plant comprising a furnace for heating an indirect heating medium to be distributed to radiators located throughout the house, a fluid fuel burner for supplying hot combustion gases to said furnace for heating said heating medium, said furnace comprising a container for fluid heating medium having end com` partments and a mid compartment spaced apart and adapted to be lled with liquid medium to be heated, a plurality of flue passages through said mid compartment connecting the spaces on either side, a tube for liquid medium extending through each passage and connecting into the end compartments, and a plurality of ue tubes extending from the space on one side of said mid compartment to and through the opposite end wall of the container.

2. A house heating plant-comprising a furnace for heating water to be distributed to radiators located throughout the house, means for supplying hot combustion gases in said furnace for heating said water, said furnace comprising a container divided into end and middle water sections by two flue gas compartments, a plurality of water tubes connecting said end sections through said compartments, a plurality of flues connecting said compartmentsthrough the middle water section, and a plurality of flues eX- tending from one of said compartments through the container, above the other compartment and through the wall of the container.

3. A housing heating furnace comprising a container for a heating medium to be heated and` supplied to house radiators, said container being divided into relatively small end and relatively large middle sections adapted to contain a body of the liquid heating medium,said sections being formed by low partitions made by two relatively narrow flue gas compartments in the lower part of said container, means for supplying hot combustion gases to one only of said compartments, ilues connecting said compartments, and flues extending at an incline from the compartment not directly receiving combustion gases above the other compartment and through the opposite end wall of the container.

4. A house heating furnace comprising a boiler chamber and a combustion chamber, said boiler chamber comprising a cylindrical chamber mounted horizontally an-d symmetrically on a vertical cylinder forming said combustion chamber, a fluid fuel burner in said combustion chamber, two flue gas compartments in the lower part Vof the said boiler chamber, one of which opens into said combustion chamber, a plurality of flue passages in said boiler chamber connecting said compartments for the passage of combustion gases in heat exchange with the water maintained therein, and water tubes in certain of said flue passages.

' 5. A house heating furnace as defined by claim 4 in which said vertical cylindrical combustion chamber includes an upper saddle shaped portion in kwhich said boiler chamber rests.

6. A house heating furnace as defined by claim 4 in which said vertical cylindrical combustion chamber comprises an annular water chamber separate from said boiler chamber for heating water for domestic use while the furnace is being used for heating the house, and a refractory lin-V ing covering a substantial portion of the wall of said combustion chamber.

'7. A house heating furnace as defined by claim 4 in which said boiler chamber is provided with a steam outlet and a condensate inlet, and valve means for converting said furnace into a domestic water heater, said means being adapted to Asimultaneously connect the condensate inlet into a source of water supply and the steam outlet into the domestic hot water line of the house.

8. A combination house heating furnace and seasonal domestic water heater, comprising a boiler chamber and a combustion chamber, said boiler chamber comprising a cylindrical chamber mounted horizontally above a combustion chamber, a fluid fuel burner in the combustion chamber operated in response to a room thermostat,

a plurality of passages in said boiler chamber for the passage of hot combustion gases in heat exchange with water maintained therein, an outlet for steam and an inlet for make up water to said boiler, means for simultaneously connecting said steam outlet into a domestic hot water line for the house and said water inlet with a water supply and for shifting the burner connection from said thermostat to an aquastat adapted to control the temperature of the hot water supplied for domestic use.

9. A combination house heating furnace and seasonal domestic water heater, comprising a boiler chamber and a combustion chamber, said boiler chamber being mounted in a position to receive heat from the combustion products produced in said combustion chamber, a fluid fuel burner in the combustion chamber operated in response to a room thermostat, an outlet for steam from and an inlet for make-up water to said boiler, means for simultaneously connecting said steam outlet into aV domestic' hot water line for the house and for connecting said water inlet with a water supply and for simultaneously shifting the burner connection from said thermostat to an aquastat adapted to control the temperature of the hot water supplied for domestic use.

10. A combination house heating furnace as defined by claim 9 in which said combustion chamber comprises an annular water chamber separate from said boiler chamber for heating water for domestic use while the furnace is being used for heating the house.

FREDERICK W. RIEHL. 

